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Screenshot: Notification of Simultaneous Page Editing
What happens if two of us are editing the same page and the other user saves before I do?
If someone else has saved the page before you, when you click 'Save', Confluence will check if there are any conflicts between your changes and theirs. If there are no conflicting changes, Confluence will merge the changes.
If there are conflicts, Confluence will display them for you and give you the option to:
For example, Alice and Bob both edit the same page at the same time.
If Alice clicks save before Bob, Bob is now effectively editing an out-of-date version of the page. When Bob clicks save, Confluence will examine his changes to see if any overlap with Alice's. If the changes do not overlap (i.e. Alice and Bob edited different parts of the page), Bob's changes will be merged with Alice's automatically.
If Bob's changes overlap with Alice's, Confluence will display an error message to Bob showing where Alice has changed the page, and giving Bob the options to overwrite Alice's changes with his own, to re-edit the document to incorporate Alice's work, or to cancel his own changes entirely, maintaining Alice's changes.